The specification of Japanese Patent No. 5079655 (Patent Document 1), and Japanese Patent Application Laid-Open (JP-A) No. 2012-51005 (Patent Document 2), for example, describe methods for manufacturing pressed components with substantially U-shaped (gutter-shaped) cross-section profiles using a press including a punch provided with a punch-side pad (inner pad) and a die provided with a die-side pad (die pad). In these pressed component manufacturing methods, a pressed component is formed by gripping a metal stock sheet with the punch-side pad projecting from the punch and the die-side pad projecting from the die, and pressing the die toward the punch side in this state. This suppresses the occurrence of spring-back in the pressed component.
Namely, in these pressed component manufacturing methods, when the die is pressed toward the punch side to form a vertical wall, since the punch-side pad projects from the punch, an inclined slack portion (linear excess portion) arises at a portion of the metal stock sheet between a shoulder of the punch-side pad and a shoulder of the punch. Specifically, the slack portion (linear excess portion) deforms in a convex curve toward a front face side of the metal stock sheet. The die-side pad and the die are then pressed further toward the punch side to form a top plate of the pressed component. When this is performed, a portion of the metal stock sheet bent by the shoulder of the punch is formed into a vertical wall pressed out toward a base end side of the vertical wall. A first moment toward the pressed component inside therefore arises at the base end side of the vertical wall of the pressed component prior to demolding (see the arrow in FIG. 5(b) of Patent Document 2).
The slack portion (linear excess portion) is ultimately squashed between the punch and the die. However, prior to being squashed, the slack portion (linear excess portion) curves and deforms into a convex curve toward the front face side of the metal stock sheet. Accordingly, after being squashed, a second moment toward the inside of the pressed component arises at both width direction edges of the top plate of the pressed component (see the arrow in FIG. 5(b) of Patent Document 2).
Moreover, prior to demolding, a third moment toward the pressed component outside arises at a ridge line portion of the pressed component (see the arrow in FIG. 5(b) of Patent Document 2). The third moment cancels out (balances out) the first and second moments, thereby suppressing spring-back in the pressed component.